Synthesis, characterization and antimicrobial application of carrageenan/TiO₂ composite materials

In this study, a highly crystalline anatase/rutile mixed phase carrageenan/TiO₂ nanocomposite with a larger surface area was synthesized via the sol-gel process and calcined at 450 °C and 650 °C. The synthesized composite materials were characterized by FTIR, XRD, SEM, EDX, TEM, BET and TGA. FTIR confirms the presence of C-Ti-O bond formation in composite. XRD analysis confirmed the presence of both rutile and anatase phases of titanium dioxide in the composite materials. SEM revealed a morphologically porous surface, and EDX confirmed the presence of titanium, oxygen, and carbon elements in the composite materials calcined at 450 °C and 650 °C. The carrageenan/TiO₂ composite material calcined at 650 °C demonstrated exceptional antibacterial activities, as it inhibited about 93 % and 82 % for the E. coli and S. aureus bacteria respectively. These findings indicate that the antimicrobial activities of composite is influenced by their crystalline nature, porosity, surface area and small size. Overall study reveals the potential application of carrageenan/TiO₂ composite material as a food additive in the food industry to inhibit the growth of bacteria and enhance the self-life of food.